The Cro-Magnon race persisted through the entire Upper Paleolithic, during the periods known as the Aurignacian, Solutrean and Magdalenian, from 25,000 to 10,000 B. C. While it is possible that the blood of this race enters somewhat into the composition of the peoples of western Europe, its influence cannot be great and the Cro-Magnons—the Nordics of their day—disappear from view with the advent of the warmer climate of recent times. It has been suggested that, following the fading ice edge north and eastward through Asia into North America, they became the ancestors of the Esquimaux but certain anatomical objections are fatal to this interesting theory. No one, however, who is familiar with the culture of the Esquimaux and especially with their wonderful skill in bone and ivory carving, can fail to be struck with the similarity of their technique to that of the Cro-Magnons. To the Cro-Magnon race the world owes the birth of art. Caverns and shelters are constantly unearthed in France and Spain, where the walls and ceilings are covered with polychrome paintings or with incised bas-reliefs of animals of the chase. A few clay models, sometimes of the human form, are also found, together with abundant remains of their chipped but unpolished stone weapons and tools. Certain facts stand out clearly, namely, that they were purely hunters and clothed themselves in furs and skins. They knew nothing of agriculture or of domestic animals, even the dog being probably as yet untamed and the horse regarded merely as an object of chase. The question of their knowledge of the principle of the bow and arrow during the Aurignacian and Solutrean is an open one but there are definite indications of the use of the arrow, or at least the barbed dart, in early Magdalenian times and this weapon was well known in the succeeding Azilian Period. The presence toward the end of this last period of quantities of very small flints called microliths has given rise to much controversy. It is possible that some of these microliths represent the tips of small poisoned arrows such as are now in very general use among primitive hunting tribes the world over. Certain grooves in some of the flint weapons of the Upper Paleolithic may also have been used for the reception of poison. It is highly probable that the immediate predecessors of the Azilians, the Cro-Magnons, perhaps the greatest hunters that ever lived, not only used poisoned darts but were adepts in trapping game by means of pitfalls and snares, precisely as do some of the hunting tribes of Africa to-day. Barbed arrowheads of flint or bone, such as were commonly used by the North American Indians, have not been found in Paleolithic deposits.